1. Field of the Invention
The present invention relates to a button apparatus employing a transceiver used for data communication with, for example, a wearable computer. In particular, the present invention relates to a button apparatus employing a transceiver that transmits and receives information by inducing an electric field in an electric-field propagating medium according to information to be transmitted and by detecting an electric field induced in the electric-field propagating medium.
2. Description of Related Art
Reduced size and improved capabilities of portable terminals have brought attention to wearable computers. FIG. 1 shows examples of wearable computers put on and used by a human. In FIG. 1, the wearable computers 1a, 1b, and 1c are provided with transceivers 3a, 3b, and 3c, respectively, and are put on, for example, the arm, shoulder, and torso of a user, to communicate data among them. Transceivers 3d and 3e are installed on, for example, the wall and floor so that they can be touched with the tip of a hand or foot of the user, to enable the wearable computers 1a, 1b, and 1c to communicate with an external personal computer (PC) 5 through the transceivers 3d and 3e and cables.
Each of the transceivers 3 used for communication among the wearable computers 1 and between the wearable computers 1 and the PC 5 utilizes a signal detection technique based on electro-optic means employing laser beams and electro-optic crystals. Namely, the transceiver 3 induces an electric field in the body of the user serving as an electric-field propagating medium according to information to be transmitted and uses the induced electric field to communicate information (Japanese Unexamined Patent Application Publication No. 2001-352298).
Now, to purchase a commodity from, for example, a vending machine, one must carry money, insert the money into the vending machine, select a commodity, and thus purchase the commodity.
In this procedure of purchasing a commodity, one encounters a problem that he or she must take various steps until getting a required commodity. The steps include taking money out of a purse, inserting the money into a vending machine, selecting a commodity, picking up change, and the like.